Fluorosurfactants

ABSTRACT

The present invention relates to novel compounds containing fluorinated end groups, to the use thereof as surface-active substances, and to processes for the preparation of these compounds.

The present invention relates to novel compounds containing fluorinatedend groups, to the use thereof as surface-active substances, and toprocesses for the preparation of these compounds.

Fluorosurfactants have an outstanding ability to reduce surface tension,which is utilised, for example, in the hydrophobicisation of surfaces,for example of textiles, paper, glass, building materials or adsorbents.In addition, it is possible to use them as interface promoter oremulsifier or viscosity reducer in paints, surface coatings oradhesives.

In general, fluorosurfactants contain perfluoroalkyl substituents, whichare broken down to perfluoroalkylcarboxylic acids (PFCAs) and -sulfonicacids (PFASs) in the environment by biological and/or other oxidationprocesses. In recent years, the accumulation of perfluoroalkylcarboxylicacids (PFCAs) and perfluoroalkylsulfonic acids (PFASs) in nature hasgiven cause for concern. PFCAs and PFASs are highly persistent compoundswhose long-chain variants (containing perfluoroalkyl chains of 8 or morecarbon atoms) have a bioaccumulative potential. They are in some casessuspected of causing health problems (G. L. Kennedy, Jr., J. L.Butenhoff, G. W. Olsen, J. C. O'Connor, A. M. Seacat, R. G. Biegel, S.R. Murphy, D. G. Farrar, Critical Review in Toxicology, 2004, 34,351-384).

Specific applications of sulfotricarballylates containing optionallyfluorinated alkyl groups or aryl groups are described in U.S. Pat. No.4,988,610, U.S. Pat. No. 6,890,608 and in A. R. Pitt et al., Colloidsand Surfaces A: Physicochemical and Engineering Aspects, 1996, 114,321-335; A. R. Pitt, Progr. Colloid Polym. Sci., 1997, 103, 307-317 andZ.-T. Liu et al., Ind. Eng. Chem. Res. 2007, 46, 22-28.

The Omnova company markets polymers whose side chains contain terminalCF₃ or C₂F₅ groups. International Patent Application WO 03/010128describes perfluoroalkyl-substituted amines, acids, amino acids andthioether acids which contain a C3-20-perfluoroalkyl group.

JP-A-2001/133984 discloses surface-active compounds containingperfluoroalkoxy chains which are suitable for use in antireflectioncoatings. JP-A-09/111,286 discloses the use of perfluoropolyethersurfactants in emulsions. DE 102005000858 A1 describes compounds whichcarry at least one terminal pentafluorosulfuranyl group or at least oneterminal trifluoromethoxy group and contain a polar end group, aresurface-active and are suitable as surfactants.

There continues to be a demand for alternative surface-activesubstances, preferably having a property profile comparable to that ofclassical fluorosurfactants and equally great chemical versatility,which are preferably not degraded to long-chain persistentfluorocarboxylic or fluorosulfonic acids on oxidative or reductivedegradation or are preferably effective as conventionalfluorosurfactants in relatively low dosage.

Novel compounds have now been found which are suitable as surface-activesubstances and preferably do not have one or more of the above-mentioneddisadvantages.

The present invention relates firstly to compounds of the formula (I)

wherethe groups Z_(i) (Z₁, Z₂ and Z₃) are, independently of one another,branched or unbranched alkyl groups or groups of the structureR_(i)(A(CR¹R²)_(ci)—(CR³R⁴)_(c′i)))_(di)—, where the respective indicesci and c′i are, independently of one another, 0-10, and di=0-5, whereR_(i) is a branched or unbranched, fluorine-containing alkyl radical, R¹to R⁴ are, independently of one another, hydrogen or a branched orunbranched alkyl group, ci and c′i are not simultaneously 0, and A=O, Sand/or N,Y₁ is an anionic polar group and Y₂ is a hydrogen atom, or vice versa,X is a cation,and at least one of the groups Z_(i) is a group of the structureR_(i)(A(CR¹R²)_(ci)—(CR³R⁴)_(c′i))_(di)—.

It is preferred for formula (I) that a) di>0 if Z₁, Z₂ and Z₃ are all agroup of the structure R_(i)(O(CH₂)_(ci))_(di) and all R_(i) areselected from CF₃CF₂CH₂—, CF₃CF₂CH₂CH₂—, CF₃CF₂CF₂CH₂— or H(CF₂)₄CH₂—and/or that b) Y₂ is not equal to OSO₃ ⁻ and X is not equal to Na⁺ or K⁺if Z₁=Z₂=Z₃ and all Z_(i) are selected from C₄F₉CH₂CH₂—, C₆F₁₃CH₂CH₂— orC₈F₁₇CH₂CH₂—.

The radicals R_(i) are branched or unbranched, fluorine-containing alkylgroups. The radicals R_(i) may be partly or perfluorinated andpreferably contain terminal perfluorinated groups. Preference is givento branched or unbranched, fluorine-containing alkyl groups having 1 to10 C atoms. Unbranched fluorine-containing alkyl groups preferablycontain 1 to 6 C atoms, in particular 1-4 C atoms. Branchedfluorine-containing alkyl groups preferably contain 3 to 6 C atoms, inparticular 3-4 C atoms. The branched fluorine-containing alkyl groupsused are preferably (CF₃)₂—CH— or (CF₃)₃—C— groups.

R¹ to R⁴ are preferably, independently of one another, hydrogen or aC₁₋₄-alkyl group, in particular H or CH₃. ci and c′i are preferably,independently of one another, an integer from the range 0 to 6, inparticular 0-3, particularly preferably 0-2, where ci and c′i are notsimultaneously 0. di is preferably an integer from the range 0 to 3,particularly preferably 1-3, in particular 1.

A is preferably equal to O or S, in particular O. In particular, thegroups Z_(i) are equal to R_(i)(O(CR¹R²)_(ci)(CR³R⁴)_(c′i))_(di)—.

Particular preference is given to compounds where R¹ to R³ are equal tohydrogen, R⁴ is equal to hydrogen or methyl, ci and c′i are,independently of one another, equal to 0-2, in particular 1, di is equalto 0-3, in particular 1-3, and A is equal to 0, where ci and c′i are notsimultaneously 0. In a preferred variant of the invention, R⁴ here isequal to methyl and the variables have these preferred meanings. Alsosuitable are compounds in which R¹ is equal to methyl and R² to R⁴ areequal to hydrogen, where the variables have the preferred meanings.

Particular preference is given to compounds of the formula (I) in whichthe fluorine-containing groups Z_(i) are equal toR_(i)(O(CH₂)_(ci))_(di)—, where the respective indices ci=2-10,preferably 2-4, in particular 2, and di=0-5, preferably 0-3,particularly preferably 1-3, in particular 1, Y₁ is an anionic polargroup, and Y₂ is a hydrogen atom, or vice versa, X is a cation, and atleast one of the groups Z_(i) is a group of the structureR_(i)(O(CH₂)_(ci))_(di)—, where preferably a) d>0 if Z₁, Z₂ and Z₃ areall a group of the structure R_(i)(O(CH₂)_(ci))_(di)— and all R_(i) areselected from CF₃CF₂CH₂—, CF₃CF₂CH₂CH₂—, CF₃CF₂CF₂CH₂— or H(CF₂)₄CH₂—,and b) Y₂ is not equal to OSO₃ ⁻ and X is not equal to Na⁺ or K⁺ ifZ₁=Z₂=Z₃ and all Z_(i) are selected from C₄F₉CH₂CH₂—, C₆F₁₃CH₂CH₂— orC₈F₁₇CH₂CH₂—.

Preference is furthermore given to compounds of the formula (I) in whichZ₁, Z₂ and Z₃ are, independently of one another,F₃C(CF₂)_(ai)(CH₂)_(bi)—(O(CH₂)_(ci))_(di)— groups, where ai=0-6,preferably 1-5, in particular 1-2, bi=1-6, preferably 1-3, in particular1-2, ci=2-10, preferably 2-4, in particular 2, and di=0-5, preferably1-3, in particular 1, where, in particular, Z₁=Z₂=Z₃. Preference is alsogiven to compounds in which ai=0, 1 or 2, preferably 1 to 2, inparticular 1, bi=1, ci=2, and di=1 or 2, in particular 1, and wherea₁+a₂+a₃>1.

If all Z₁, Z₂ and Z₃ are selected from CF₃CF₂CH₂—, CF₃CF₂CH₂CH₂—,CF₃CF₂CF₂CH₂— or H(CF₂)₄CH₂—, di in formula (I) is preferably greaterthan 0. If Z₁=Z₂=Z₃ and all Z_(i) are selected from C₄F₉CH₂CH₂—,C₆F₁₃CH₂CH₂— or C₈F₁₇CH₂CH₂—, Y₂ is not equal to OSO₃ ⁻, and X is notequal to Na⁺ or K⁺.

In an embodiment of the invention, the compounds according to theinvention can be in the form of mixtures, in which the individualcompounds have different values for ci, c′i and/or di.

The compounds of the formula (I) according to the invention may containone or more fluorinated groups Z_(i) according to the invention. Thecompounds preferably contain two or three fluorinated groups Z_(i),particular preference being given to those containing three fluorinatedgroups Z_(i).

The three substituents Z₁, Z₂ and Z₃ may all be identical, may all bedifferent or two of them may be identical and one of them different,with the proviso that Z₁, Z₂ and Z₃ are not all simultaneouslyunfluorinated, branched or unbranched alkyl radicals. Preferredcompounds are those in which two of Z₁, Z₂ and Z₃ or all of Z₁, Z₂ andZ₃ are identical, in particular equal to the preferredR_(i)(O(CR¹R²)_(ci)(CR³R⁴)_(ci))_(di)— groups described. Very particularpreference is given here to the following fluorine-containing alkylradicals: CF₃CH₂—, CF₃CF₂CH₂—, CF₃CF₂CF₂CH₂—, CF₃CF₂CH₂CH₂—,CF₃CF₂CH₂CH₂CH₂—, CF₃CFHCF₂CH₂—, (CF₃)₂CH—, (CF₃)₃C—, CF₃(CF₂)₃—CH₂CH₂—,CF₃(CF₂)₅CH₂CH₂—, CF₃(CF₂)₄CH₂—. The compounds preferably includefluorine-containing alkyl radicals having at most 3 fluorine-carryingcarbon atoms. Particularly preferred compounds of the formula (I) whereZ₁=Z₂=Z₃ are those in which ci or c′i is equal to 0 to 3, in particular0-2, and di>0, where ci and c′i are not simultaneously 0. Compoundsaccording to the invention where di is equal to 1 to 3, in particular 1,are especially preferred.

If the compounds contain unfluorinated end groups Z₁, Z₂ and Z₃, theseare preferably, independently of one another, linear or branched alkylhaving 1 to 20 C atoms, preferably 1 to 10 C atoms. In particular, Z₁,Z₂ and Z₃ are, independently of one another, linear alkyl having 3 to 10C atoms, particularly preferably having 3 to 8 C atoms. If two of thegroups Z₁, Z₂ and Z₃ are unfluorinated, these two groups are preferablyidentical.

In a preferred group of compounds to be employed in accordance with theinvention or compounds according to the invention, Y₁ and Y₂, where oneof the two is equal to a hydrogen atom, stand for an anionic polar groupselected from —COO₃ ⁻, —SO₃ ⁻, —OSO₃ ⁻, —OPO₃ ²⁻,—(OCH₂CH₂)_(s)—O—(CH₂)_(t)COO⁻, —(OCH₂CH₂)_(s)—O—(CH₂)_(t)SO₃ ⁻,—(OCH₂CH₂)_(s)—O—(CH₂)_(t)OSO₃ ⁻, —(OCH₂CH₂)_(s)—O—(CH₂)_(t)—PO₃ ²⁻—,—(OCH₂CH₂)_(s)—O—(CH₂)_(t)—OPO₃ ²⁻ or for the formulae A to C,

where s stands for an integer from the range 1 to 1000, t stands for aninteger selected from 1, 2, 3 or 4, and w stands for an integer selectedfrom 1, 2 or 3.

The preferred anionic groups here include, in particular, —COO⁻, —SO₃ ⁻,—OSO₃ ⁻, —PO₃ ²⁻, —OPO₃ ²⁻, the sub-formula A, and—(OCH₂CH₂)_(s)—O—(CH₂)_(t)—COO⁻, —(OCH₂CH₂)_(s)—O—(CH₂)_(t)—SO₃ ⁻ and—(OCH₂CH₂)_(s)—O—(CH₂)_(t)—OSO₃ ⁻, where each individual one of thesegroups taken alone may be preferred.

The very particularly preferred anionic groups here include —SO₃ ⁻,—OSO₃ ⁻, —PO₃ ²⁻ or OPO₃ ²⁻, in particular —SO₃ ⁻. Particular preferenceis given to compounds in which Y₁ is a sulfonate group —SO₃ ⁻, and Y₂ isa hydrogen atom.

X is preferably a monovalent cation, in particular H⁺, an alkali metalcation or NR₄ ⁺, where R=H⁺ or C1-C6-alkyl, and all R may be identicalor different. X is particularly preferably Na⁺, K⁺ or NH₄ ⁺, especiallypreferably Na⁺.

Preferred compounds of the formula (I) are, in particular, compounds inwhich all variables have the preferred meanings. Preference isexplicitly given to compounds in whichZ₁=Z₂=Z₃=F₃C(CF₂)_(ai)(CH₂)_(bi)(O(CH₂)_(ci))_(di)—, where ai=1-2,bi=1-2, ci=2, di=1-3, Y₁ or Y₂ is a sulfonate group —SO₃ ⁻, and X=Na⁺.

Particular preference is given to compounds of the formula (Ia) or (Ib):

where Z₁=Z₂=Z₃ and all Z_(i) are selected from R_(i)(O(CH₂)_(ci))_(di)—,where ci=2, di=1-3, and R_(i)=CF₃CF₂CH₂— or CF₃CF₂CF₂CH₂—.

The compounds of the formula (I) according to the invention are referredto in the present invention as sulfotricarballylates and are based onesters of aconitic acid, onto the double bond of which a sulfonate grouphas been added. In particular, sulfotricarballylates containing threefluorinated end groups according to the invention are preferred. Thecompounds of the formula (I) according to the invention can also be inthe form of mixtures, particularly also in the form of isomer mixtures(constitutional and/or configurational isomer mixtures). In particular,diastereomer and/or enantiomer mixtures are possible.

Examples of preferred compounds according to the invention are:

where compounds of the formulae Ia-1 and Ia-2 are particularlypreferred.

Advantages of the compounds according to the invention may be, inparticular:

-   -   a surface activity which is equal or superior to that of        conventional hydrocarbon surfactants with respect to efficiency        and/or effectiveness,    -   biological and/or abiotic degradability of the substances        without the formation of persistent perfluorinated degradation        products, such as PFOA (perfluorooctanoic acid) or PFOS        (perfluorooctanesulfonate),    -   weak foaming action and/or low foam stabilisation,    -   good processability in formulations and/or    -   storage stability.

The compounds according to the invention preferably have particularsurface activity. The compounds of the formula (I) according to theinvention may have significantly improved environmental propertiescompared with the prior-art fluorosurfactants since they do not undergoeither chemical or biological degradation to long-chain PFCAs or PFASs.

The present invention relates secondly to the use of the compoundsaccording to the invention, in particular the preferred compounds of theformula (I), as surface-active agents, for example for improving theflow behaviour and wetting ability of coating formulations.

The preferred embodiments of the compounds according to the inventiondescribed above can particularly advantageously be used here.Sulfotricarballylates which contain two or three, in particular three,fluorinated groups according to the invention are preferably used.Compounds of the formulae (Ia) and/or (Ib) are preferably used. Thecompounds according to the invention can also be used in the form ofmixtures, particularly also in the form of isomer mixtures(constitutional and/or configurational isomer mixtures). In particular,diastereomer and/or enantiomer mixtures are possible.

Areas of application are, for example, the use of the compoundsaccording to the invention as additives in surface-coating preparations,such as paints, coatings, protective coatings, speciality coatings inelectronic or semiconductor applications (for example photoresists, topantireflective coatings, bottom antireflective coatings) or in opticalapplications (for example photographic coatings, coatings of opticalelements), in polishes and waxes (in particular for furniture, floorsand automobiles), or in additive preparations for addition tocorresponding preparations.

For use, the compounds according to the invention are usuallyincorporated into correspondingly designed preparations. The presentinvention likewise relates to corresponding compositions comprising atleast one compound according to the invention. Such compositionspreferably comprise a vehicle which is suitable for the particularapplication and optionally further active substances and/or optionallyassistants. Preferred compositions here are paint and surface-coatingpreparations and printing inks.

In particular, the present invention also relates to water-basedsurface-coating formulations which comprise at least one of thecompounds according to the invention, alone or mixed with othersurfactants. Preference is given to the use of surface-coatingformulations based on the following synthetic film formers:

-   -   polycondensation resins, such as alkyd resins,        saturated/unsaturated polyesters,    -   polyamides/imides, silicone resins; phenolic resins; urea resins        and melamine resins,    -   polyaddition resins, such as polyurethanes and epoxy resins,    -   polymerisation resins, such as polyolefins, polyvinyl compounds        and polyacrylates.

In addition, the compounds according to the invention are also suitablefor use in surface coatings based on natural products and modifiednatural products. Preference is given to surface coatings based on oils,polysaccharides, such as starch and cellulose, and also based on naturalresins, such as cyclic oligoterpenes, polyterpenes and/or shellac. Thecompounds according to the invention can be used both in physicallyhardening (thermoplastics) and in crosslinking (elastomers andthermosets) aqueous surface-coating systems. The compounds according tothe invention preferably improve the flow and wetting properties of thesurface-coating systems.

A further area of application of the compounds according to theinvention is in processes for the preparation of polymers, in particularfluoropolymers. Important industrial methods for the preparation offluoropolymers, such as, for example, polytetrafluoroethylene (PTFE),are, for example, emulsion and suspension polymerisation. Suspension andemulsion polymerisation processes are standard polymerisation processeswhich are well known to the person skilled in the art. In suspension andemulsion polymerisation processes, the system always comprises at leastfour constituents: (predominantly) water-insoluble monomer, water,dispersant or emulsifier and initiator. The performance of the saidpolymerisation processes is familiar to the person skilled in the art.In these processes, the polymer is prepared in an autoclave whichcontains water, the corresponding, usually gaseous, monomer(s),initiator(s), surfactant(s) and other assistant(s), with stirring andconstant temperature and pressure control. The compounds according tothe invention are suitable as surfactants for keeping the veryhydrophobic fluoropolymer droplets or particles dispersed in the aqueoussolution.

In addition, the compounds according to the invention can be employed inhydrophobicising agents, oleophobicising agents, wetting/flow-controlagents, spot and soiling protectors/cleaning agents, stain releases,antifogging agents, lubricants, antifoams, deaerators, dryingaccelerators, abrasion resistance and mechanical wear enhancers, andantistatics, in particular in the treatment of textiles (in particularclothing, carpets and carpeting, upholstery in furniture andautomobiles) and hard surfaces (in particular kitchen surfaces,sanitaryware, tiles, glass), non-woven textile materials, leatherware,papers and cardboard, wood and wood-based materials, mineral substrates,such as stone, cement, concrete, plaster, ceramics (glazed and unglazedtiles, stoneware, porcelain) and glasses, and for plastics and metallicsubstrates. For metallic substrates, the claims additionally also relateto the use in anticorrosion agents. For plastics and moulds for plasticsprocessing, the claims additionally also relate to the use inmould-release agents. In the case of cleaning agents and spot removers,the claims additionally also relate to the use as detergent or soilingemulsifier and dispersant.

The compounds according to the invention can furthermore be used asantimicrobial active substance, in particular as reagent forantimicrobial surface modification.

A further area of application of the compounds according to theinvention is in additives or in additive preparations in printing inks,having one or more of the following functions: antifoam, deaerator,friction-control agent, wetting agent, flow-control agent, pigmentcompatibility enhancer, print resolution enhancer, drying accelerator.

The compounds according to the invention can also be used as foamstabilisers and/or for supporting film formation, in particular inaqueous film-forming fire-extinguishing foams, both synthetic andprotein-based, also for alcohol-resistant formulations (AFFF andAFFF-AR, FP, FFFP and FFFP-AR).

The compounds according to the invention can furthermore be employed asadditives in polymeric materials (plastics), having one or more of thefollowing functions: lubricant, internal friction reducer, UVstabiliser, hydrophobicising agent, oleophobicising agent, spot andsoiling protector, coupling agent for fillers, flameproofing agent,migration inhibitor (in particular against migration of plasticisers),antifogging agent.

In addition, the compounds according to the invention are also suitablefor use as additives in liquid media for cleaning, etching, reactivemodification and/or substance deposition on metal surfaces (inparticular also electrocoating and anodisation) or semiconductorsurfaces (in particular for semiconductor photolithography: developer,stripper, edge bead remover, etching agent and cleaning agent), aswetting agent and/or deposited film quality enhancer.

In addition, the compounds which can be used in accordance with theinvention as surfactant are suitable for washing and cleaningapplications, and for use as additives/surfactants in cosmetic products,such as, for example, hair and body care products (for example shampoos,hair rinses and hair conditioners), foam baths, creams or lotions,having one or more of the following functions: emulsifier, wettingagent, foaming agent, lubricant, antistatic, skin grease resistanceenhancer.

The compounds according to the invention are furthermore used asadditives in herbicides, pesticides and fungicides, having one or moreof the following functions: substrate wetting agent, adjuvant, foaminhibitor, dispersant, emulsion stabiliser. In addition, the compoundsaccording to the invention can also be used as additives in de-icingagents or anti-icing agents.

In addition, the compounds according to the invention are suitable asadditives in preparations for ore processing, in particular flotationand leaching solutions, having one or more of the following functions:wetting agent, foaming agent, foam inhibitor, and as additives in agentsfor the stimulation of oil wells, having one or more of the followingfunctions: wetting agent, foaming agent, emulsifier.

A further area of application of the compounds according to theinvention is in the use as additives in adhesives, having one or more ofthe following functions: wetting agent, penetrant, substrate adhesionenhancer, antifoam.

The compounds according to the invention can furthermore be employed asadditives in greases and hydraulic fluids, having one or more of thefollowing functions: wetting agent, corrosion inhibitor. In the case ofgreases, the claims additionally also relate to the use as dispersant(in particular for fluoropolymer particles).

The compounds according to the invention can also be used as additivesin putties and filling compositions, having one or more of the followingfunctions: hydrophobicising agent, oleophobicising agent, soilingprotector, weathering resistance enhancer, UV stabiliser, agent againstsilicone bleeding.

The present invention relates to all uses mentioned here of compounds tobe employed in accordance with the invention. The respective use ofsurfactants for the said purposes is known to the person skilled in theart, and consequently use of the compounds to be employed in accordancewith the invention will present no problems. The compounds of theformula (I) according to the invention are preferably used in paint andcoating preparations, printing inks and waxes, as well as polishes.Particular preference is given to the use in paint and coatingpreparations.

The use of compounds of the formula (I), in particular the compounds ofthe formula (I) described as preferred above, in paint and coatingpreparations is particularly advantageous. Compounds in which the groupsZ_(i) are equal to R_(i)(O(CH₂)_(ci))_(di)—, where the respectiveindices ci=2-10, preferably 2-4, in particular 2, and di=0-5, preferably1-3, in particular 1, are preferred here. Compounds of the formula (I)in which Z₁=Z₂=Z₃=F₃C(CF₂)_(ai)—(CH₂)_(bi)(O(CH₂)_(ci))_(di)—, whereai=0-6, preferably 1-5, in particular 1-2, bi=1-6, preferably 1-3, inparticular 1-2, ci=2, di=1-3, preferably 1, Y₁ or Y₂ is equal to asulfonate group —SO₃ ⁻, and X=Na⁺, are particularly preferred. Inparticular, compounds of the formulae Ia-1 to Ia-6 are suitable for usein paint and coating preparations, particularly those of the formulaeIa-1 and Ia-2.

The compounds of the formula (I) according to the invention canpreferably be prepared by esterification of aconitic acid or theanhydride or acid chloride or of citric acid using one or more alcoholsZ_(i)OH (II) followed by an addition reaction, preferably of sodiumhydrogensulfite.

Z_(i) is an unfluorinated, branched or unbranched, alkyl group or agroup of the structure R_(i)(A(CR¹R²)_(ci)(CR³R⁴)_(ci))_(di)—, where therespective indices ci and c′i are, independently of one another, 0-10,and di=0-5, where R_(i) is a branched or unbranched, fluorine-containingalkyl radical, R¹ to R⁴ are, independently of one another, hydrogen or abranched or unbranched alkyl group, ci and c′i are not simultaneously 0,and A=O, S and/or N. Z_(i) preferably encompasses the variablesdescribed for the preferred compounds of the formula (I), in particularan F₃C(CF₂)_(ai)(CH₂)_(bi)(O(CH₂)_(ci))_(di)— group, where ai=0-6,bi=1-6, ci=2-10, and di=0-5. ai is preferably equal to 1 or 2, bi ispreferably equal to 1 to 3, in particular 1 to 2. ci is preferably equalto 2 to 4, in particular 2. di is preferably equal to 1 to 3, inparticular 1.

Preference is given to the use of alcohols containingF₃C(CF₂)_(ai)(CH₂)_(bi)—(O(CH₂)_(ci))_(di)— groups, where one or alsovarious alcohols can be reacted as a mixture or in steps. Preferably,only one alcohol is used, in particular.

The esterification can also be carried out in a mixture withunfluorinated, branched or unbranched alcohols or in steps using variousalcohols. The unfluorinated, branched or unbranched alcohols arepreferably those containing linear or branched alkyl having 1 to 20 Catoms, preferably 1 to 10 C atoms. Particular preference is given toalcohols having 3 to 10 C atoms, particularly preferably having 3 to 8 Catoms.

The present invention thus relates thirdly to a process for thepreparation of compounds of the formula (I), in particularsulfotricarballylates, which contain two or three end groups which arefluorinated in accordance with the invention.

The alcohols used are commercially available and/or their preparation isfamiliar to the person skilled in the art (Heilmann et al. J. FluorineChem. 1992, 59, 387; Janulis et al. U.S. Pat. No. 5,157,159 (1992)).

The aconitic esters are preferably synthesised in the presence of aconventional catalyst, such as, for example, toluene-4-sulfonic acidmonohydrate:

The aconitic esters can furthermore preferably be synthesised startingfrom citric acid in the presence of a conventional catalyst, such as,for example, sulfuric acid. It is also possible to prepare thecorresponding citric acid esters (IV).

In a second step, the group Y is then introduced by an addition reactiononto the double bond of the aconitic esters or derivatisation of the OHgroup of the citric acid esters by methods familiar to the personskilled in the art. The following scheme shows by way of example thesynthesis of the sulfotricarballylates by the addition reaction ofsodium hydrogensulfite, which can be carried out under conditions knownto the person skilled in the art:

The formula (III) reproduces the presence of Z/E double-bond isomers.Further compounds according to the invention can be prepared analogouslyto the illustrative reactions shown above. Further compounds accordingto the invention can also be prepared by other methods known from theliterature and known per se to the person skilled in the art. Inparticular, other esterification catalysts can be used.

The present invention relates fourthly to compounds of the formula(III), which occur as intermediates in the above-described syntheses ofthe compounds of the formula (I) according to the invention:

wherethe groups Z_(i) (Z₁, Z₂ and Z₃) are, independently of one another,branched or unbranched alkyl groups or groups of the structureR_(i)(A(CR¹R²)_(ci)—(CR³R⁴)_(c′i))_(di)—, where the respective indicesci and c′i are, independently of one another, 0-10, preferably 0-6, inparticular 0-2, and di=0-5, where R_(i) is a branched or unbranched,fluorine-containing alkyl radical, R¹ to R⁴ are, independently of oneanother, hydrogen or a branched or unbranched alkyl group, ci and c′iare preferably not simultaneously 0, A=O, S and/or N, and at least oneof the groups Z_(i) is a group of the structureR_(i)(A(CR¹R²)_(ci)(CR³R⁴)_(c′i))_(di)—.

Preferred compounds of the formula (III) are those in which Z₁, Z₂ andZ₃ are, independently of one another,F₃C(CF₂)_(ai)(CH₂)_(bi)(O(CH₂)_(ci))_(di)— groups, where ai=0-6, inparticular ai=1-5, preferably 1-2, bi=1-6, preferably 1-3, in particularbi=1-2, ci=2-10, in particular ci=2, and di=0-5, in particular di=1.Particularly suitable compounds are those where Z₁=Z₂=Z₃.

Preference is also given to compounds in which ai=0, 1 or 2, preferably1 or 2, in particular 1, bi=1, ci=2, and di=1 or 2, in particular 1, andwhere a₁+a₂+a₃>1.

The present invention relates fifthly to the use of the compounds of theformula (III) as monomers or comonomers in the synthesis of fluorinatedpolymers.

The disclosures in the cited references are hereby expressly also partof the disclosure content of the present application. The followingexamples explain the present invention in greater detail withoutrestricting the scope of protection.

EXAMPLES Example 1 Synthesis of the sulfotricarballylate of the Formula(Ia-1) a) Esterification

The alcohol used is prepared as described in the literature (Heilmann etal. J. Fluorine Chem. 1992, 59, 387; Janulis et al. U.S. Pat. No.5,157,159 (1992)). A mixture of 72.4 mmol of alcohol, 18.1 mmol ofaconitic acid (90%, Alfa Aesar) and 3.6 mmol of toluene-4-sulfonic acidmonohydrate (Merck KGaA) in 40 ml of toluene is subsequently stirredunder reflux for 48 hours. The water liberated during the reaction isremoved with the aid of a water separator. The reaction is quenchedusing water. The mixture is subsequently extracted with toluene, and thecombined organic phases are washed with water, dried over sodium sulfateand filtered. The solvent is distilled off in a rotary evaporator.

Purification: column chromatography over silica gel;

Eluent: toluene/ethyl acetate 1/2

Substance: C₂₁H₂₁F₁₅O₉, M=702.362 g/mol

¹H-NMR (400 MHz; in DMSO-d₆):

6.84 (s); 4.38-4.09 (m); 3.92-3.74 (m) ppm.

¹⁹F-NMR (376 MHz; in DMSO-d₆):

−82.85-−83.02 (m); −122.79-−122.94 (m) ppm.

MS (EI, 70 eV) m/e:

553 (10%); 509 (10%); 221 (15%); 177 (100%).

b) Addition Reaction

68 ml of sodium hydrogensulfite solution (39% in water, Merck KGaA) (338mmol) are added dropwise at 50° C. to a solution of 13.5 mmol of thetriester in 45 ml of 1,4-dioxane (Merck KGaA), and the mixture isstirred under reflux. After the dropwise addition, the reactiontemperature is held at 88° C. for 65 hours. After 24 hours and 48 hours,23 ml of sodium hydrogen-sulfite solution (39% in water, Merck KGaA)(113 mmol) are again added dropwise each time. The solvent is removed ina rotary evaporator. The crude product is subsequently taken up indiethyl ether (Merck KGaA), stirred and filtered. The filter residue isagain washed by stirring and filtered. The diethyl ether phases arecombined, and the organic solvent is removed in a rotary evaporator.

Substance: C₂₁H₂₂F₁₅O₁₂SNa; M=806.424 g/mol

¹H-NMR (400 MHz; in DMSO-d₆):

4.31-4.06 (m); 4.00 (d); 3.95 (d); 3.88-3.71 (m); 3.68-3.54 (m);3.48-3.37 (m); 3.36-3.00 (m); 2.92 (d); 2.87 (d) ppm.

¹⁹F-NMR (376 MHz; in DMSO-d₆):

−83.23-−83.40 (m); −123.16-−123.55 (m) ppm.

MS (FIA-ESI) m/e:

Pos. mode: 807 (M+H)⁺

Neg. mode: 783 (M−Na)⁻

Example 2 Determination of the Static Surface Tension

The static surface tensions γ of aqueous surfactant solutions havingvarious concentrations c (percent by weight) are determined.

Instrument: Sinterface tensiometer (model PAT1)

Temperature of the measurement solutions: room temperature

Measurement method employed: measurement of the surface tension onhanging droplets against air. The principal radii of curvature (r₁ andr₂) of the ellipsoids (droplets) are determined here by droplet contouranalysis. Since the pressure difference (Δp) between the outside andinside of an interface is indirectly proportional to the radii ofcurvature, the surface tension can be calculated from the followingcorrelation:

${\Delta \; p} = {\gamma \left( {\frac{1}{r_{1}} + \frac{1}{r_{2}}} \right)}$

Instrument settings: droplet volumes 7-10 mm³; measurement time1500-3600 s; 1.5 pictures/s, droplet density=1 g/cm³.

The measurement values are shown in Table 1. FIG. 1 shows the staticsurface tension as a function of the concentration of thesulfocarballylate according to Example 1b).

TABLE 1 c [%] γ[mN/m] 0.001 49.4 0.013 35.6 0.127 28.5 0.240 24.7 0.30822.9 0.370 22.6 0.414 22.3 0.451 21.9 0.485 21.2 0.513 20.9 0.610 21.21.265 20.7

Example 3 Determination of the Dynamic Surface Tension

The dynamic surface tension γ of a 0.1% (percent by weight) aqueoussolution of compound 1b) is determined.

Measurement method employed: measurement of the surface tension usingthe bubble pressure method

Instrument: SITA tensiometer (model t 60)

Temperature of the measurement solutions: 21° C.±0.2° C.

In the measurement of the dynamic surface tension, air bubbles areforced through a capillary into the surfactant solution at differentrates. From the resultant pressure change, the surface tension can bedetermined as a function of the bubble life using the followingequation:

$\gamma = \frac{r\left( {p_{\max} - {\rho \cdot g \cdot h}} \right)}{2}$

p_(max)=maximum pressure, ρ=density of the liquid, h=immersion depth,r=radius of the capillary

The measurement values are shown in Table 2. FIG. 2 shows the dynamicsurface tension as a function of the bubble life for compound 1b).

TABLE 2 Bubble life [ms] γ[mN/m] 30 56.1 38 51.5 50 47.7 65 44.1 82 41.9113 40 141 38.8 189 37.9 243 37.2 306 36.3 414 35.7 533 35.6 674 35.2924 34.6 1299 34.2 1727 33.9 2200 33.7 2507 33.5 3204 33.5 4102 32.95473 32.9 7012 32.7 9132 32.5 11537 32.3 15707 32.1 19795 31.8 2652931.5 35138 31.4 44790 31.3 58574 31

Example 4 Antipitting Test in a Polyurethane Water-Borne Surface Coating

A surface coating is prepared from the raw materials according to Table3 in which surface defects (pits) are generated specifically byoverdosing the antifoam BYK 023. A highly concentrated solution (95% byweight) of the sulfotricarballylate according to Example 1b in DowanolPM (Dow Chemicals) is incorporated into the surface coating in variousamounts and compared in efficacy to the 0 sample (withoutsulfotricarballylate).

TABLE 3 Raw materials for surface-coating formulation Product FunctionManufacturer Bayhydrol XP Binder Bayer 2470 Bayhydur 304 PUR curingBayer agent Methoxybutyl Solvent VWR acetate BYK-023 Antifoam BYK ChemieBlue pigment Contrast to sub- BASF paste strate

In the preparation of the contaminated surface-coating sample, firstlybinder, pigment paste and water are initially introduced (Table 4a; PEbeaker: 860 ml), and some of the initially introduced mixture issubsequently completed (Table 4b; PE beaker 350 ml).

TABLE 4a Initially introduced components 1 Formulation Dissolver/stirrerPos. Raw material [g] disc setting 1 Bayhydrol XP 2470 271.18 400 rpm; 2Pigment paste 8 10 min; 80 mm 3 H₂O 27.28

TABLE 4b Completion Formulation Dissolver/stirrer Pos. Raw material [g]disc setting 4 Initially introduced 128.55 400 rpm; mixture 10 min; 80mm 5 Bayhydur 304 41.03 6 Methoxybutyl ace- 10.27 tate 7 H₂O 19.62 8 BYK023 0.14 600 rpm; 10 min; 60 mm

For incorporation of the surfactant solution, the latter is firstlyinitially introduced (PE beaker, 175 ml), and the amount of surfacecoating is subsequently based on the weight of surfactant. Three testcoatings having a different surfactant content or without surfactant areprepared (Table 5).

TABLE 5 Incorporation of the surfactant solution Surface- Weight ofWeight of C* sur- Dissolver/ coating surfactant surface factant stirrerdisc sample solution [g] coating [g] [%] setting 1 — — 0 sample — 20.0544 37.42 0.06 900 rpm; 5 min; 40 mm 3 0.2064 47.39 0.19 900 rpm; 5min; 40 mm *Surfactant content based on the total amount ofsurface-coating sample

The surface coatings are applied to white paint cards (219×286 mm;manufacturer: Leneta) with the aid of an automatic film applicator withvacuum suction (Byk Gardner E-2101) with a film applicator frame(Erichson model 360; capacity: 4 ml of surface coating; metering: 20 mlspraying; drawing speed: 50 mm/s; wet layer thickness: 30 μm).

Surface-coating sample 2 is virtually free of surface defects (pits) andsurface-coating sample 3 is completely free of surface defects (pits),whereas surface-coating sample 1 exhibits numerous surface defects(pits).

FIGS. 1 and 2 show the static and dynamic surface tension respectivelyfor compound 1b).

Example 5 Synthesis of the sulfotricarballylate of the Formula (Ia-2)

The sulfotricarballylate of the formula (Ia-2) is prepared by theprocess described in Example 1.

Empirical formula: C₂₄H₂₂F₂₁O₁₂SNa, M=956.447 g/mol

¹H-NMR (300 MHz; in DMSO-d₆):

4.26-4.02 (m); 3.91 (dd); 3.82-3.67 (m); 3.63-3.46 (m); 3.44-3.30 (m);3.25-2.98 (m);

2.89-2.77 (m) ppm.

¹⁹F-NMR (282 MHz; in DMSO-d₆):

−80.42 to −80.82 (m); −127.11 to −127.50 (m); −119.79 to −120.88 (m)ppm.

MS (FIA-ESI) m/e:

Neg. mode: 933 (M−Na)⁻

Both the static surface tension as described in Example 2 and thedynamic surface tension as described in Example 3 are subsequentlydetermined. The results are shown in Tables 6 and 7.

TABLE 6 c [%] γ[mN/m] 0.0001 54.2 0.0011 30.6 0.0018 27.8 0.0055 25.80.011 21.5 0.016 18.4 0.038 17.8 0.045 17.8 0.050 17.8 0.024 17.8 0.10017.6 0.994 17.6

TABLE 7 Bubble life [ms] γ[mN/m] 31 68 38 66.3 49 62.7 65 58.4 83 52.1108 44.7 144 34.8 191 27.7 241 25 325 22.9 406 20.4 522 19.3 697 18.9859 18.8 1163 18.3 1811 18.1 2250 17.8 2590 17.8 3223 17.6 4028 17.45615 17.6 7247 17.5 8998 17.4 12741 17.2 16566 17.5 19736 17.1 2703517.3 34338 16.9 43556 16.8 56679 16.8

Example 6 Synthesis of the sulfotricarballylate of the Formula (Ia-3)

The sulfotricarballylate of the formula (Ia-3) is prepared by theprocess described in Example 1.

Empirical formula: C₂₁H₁₉F₁₈O₁₂SNa, M=860.395 g/mol

¹H-NMR (400 MHz; in DMSO-d₆):

5.48-5.37 (m); 5.35-5.21 (m); 4.30-4.09 (m); 4.07-3.90 (m); 3.57-3.46(m); 3.40-3.32 (m); 3.15-3.05 (m); 2.82 (dd) ppm.

¹⁹F-NMR (376 MHz; in DMSO-d₆):

−73.53 to −73.85 (m) ppm.

MS (LC-ESI-MS negative):

RT: 9.05 (837 [M−H]⁻)

Both the static surface tension as described in Example 2 and thedynamic surface tension as described in Example 3 are subsequentlydetermined. The results are shown in Tables 8 and 9.

TABLE 8 c [%] γ[mN/m] 0.0001 57.9 0.001 52.5 0.01 44.0 0.10 29.2 0.2525.4 0.53 22.7 1.03 21.7 1.22 21.3 2.46 21.0 4.74 20.8

TABLE 9 Bubble life [ms] γ[mN/m] 57 31 53.1 38 47.8 52 44.7 64 42 8539.8 111 38.7 144 37.4 190 36.5 243 36 324 35.5 423 35.2 512 34.9 70634.6 938 34.4 1209 34 1773 33.8 2145 33.7 2498 33.6 3277 33.5 4172 33.25331 33.1 7431 33.1 9743 33.4 11981 32.7 15946 32.2 20560 32.1 2747632.1 35812 32 47092 31.9 60416

Example 7 Synthesis of the sulfotricarballylate of the Formula (Ia-4)

The sulfotricarballylate of the formula (Ia-4) is prepared by theprocess described in Example 1.

Empirical formula: C₂₄H₁₆F₂₇O₉SNa, M=1016.391 g/mol

¹H-NMR (400 MHz; in DMSO-d₆):

4.51-4.25 (m); 4.14 (d); 4.08 (d); 3.70-3.59 (m); 3.55-3.45 (m);3.37-3.15 (m); 2.97 (dd) ppm.

¹⁹F-NMR (376 MHz; in DMSO-d₆):

−80.95 to −81.39 (m); −113.39 to −114.00 (m); −124.36 to −124.82 (m);

−126.02 to −126.38 (m) ppm.

MS (LC-ESI-MS negative):

RT: 10.60 (993 [M−H]⁻)

Both the static surface tension as described in Example 2 and thedynamic surface tension as described in Example 3 are subsequentlydetermined. The results are shown in Tables 10 and 11.

TABLE 10 c [%] γ[mN/m] 0.0001 71.6 0.0003 66.3 0.0006 40.8 0.0010 22.40.0018 17.6 0.0020 17.5 0.0024 17.0 0.005 16.8 0.01 16.6 0.10 16.3 0.9316.2

TABLE 11 Bubble life [ms] γ[mN/m] 31 72.3 38 72.2 49 72.1 68 72.1 8472.2 112 71.8 145 71.9 190 71.6 244 71.3 320 71.3 391 71 521 71 706 70.5869 70.2 1224 70.4 1613 70 2102 70.3 2572 70.2 3329 69.5 4290 69.2 550668.5 6850 67.5 9319 65.7 11716 64.2 15108 60 19279 55.8 24035 50.2 3086540.8 40016 32.1 55320 24.4

Example 8 Synthesis of the sulfotricarballylate of the Formula (Ia-5)

The sulfotricarballylate of the formula (Ia-5) is prepared by theprocess described in Example 1.

Empirical formula: C₃₀H₁₆F₃₉O₉SNa, M=1316.436 g/mol

¹H-NMR (300 MHz; in DMSO-d₆):

4.53-4.25 (m); 4.13 (d); 4.06 (d); 3.69-3.60 (m); 3.54-3.46 (m); 3.27(ddd); 3.04-2.96 (m); 2.61-2.42 (m) ppm.

¹⁹F-NMR (282 MHz; in DMSO-d₆):

−81.74 to −82.27 (m); −113.61 to −114.41 (m); −122.50 (s); −123.29 to−124.35 (m);

−126.74 to −127.31 (m) ppm.

MS (LC-ESI-MS negative):

RT: 11.91 (1293 [M−H]⁻)

Both the static surface tension as described in Example 2 and thedynamic surface tension as described in Example 3 are subsequentlydetermined. The results are shown in Tables 12 and 13.

TABLE 12 c [%] γ[mN/m] 0.0001 71.9 0.001 71.5 0.01 71.4 0.10 52.9 0.9854.5

TABLE 13 Bubble life [ms] γ[mN/m] 31 72.8 38 72.9 49 72.8 64 72.8 8672.9 110 72.7 146 72.7 187 72.9 244 72.9 319 73.1 393 73.2 524 73.3 71573.4 890 73.3 1257 73.1 1614 72.9 2142 73 2536 73 3283 72.8 4222 72.85476 72.8 7128 72.9 9188 72.7 11868 72.7 15248 72.5 20919 72.5 2672072.3 34303 72.3 44207 72.1 60491 72.2

Example 9 Synthesis of the sulfotricarballylate of the Formula (Ia-6)

The sulfotricarballylate of the formula (Ia-6) is prepared by theprocess described in Example 1.

Empirical formula: C₃₀H₂₂F₃₃O₁₂SNa, M=1256.492 g/mol

¹H-NMR (400 MHz; in DMSO-d₆):

4.28-4.05 (m); 3.91 (d); 3.84 (d); 3.82-3.69 (m); 3.51-3.45 (m);3.39-3.30 (m); 3.25-3.09 (m); 3.02 (dd); 2.83 (dd) ppm.

¹⁹F-NMR (376 MHz; in DMSO-d₆):

−80.94 to −81.23 (m); −119.39 to −119.96 (m); −123.34 to −123.87 (m);−126.30 to −126.76 (m) ppm.

MS (LC-ESI-MS negative):

RT: 11.38 (1233 [M−H]⁻)

Both the static surface tension as described in Example 2 and thedynamic surface tension as described in Example 3 are subsequentlydetermined. The results are shown in Tables 14 and 15.

TABLE 14 c [%] γ[mN/m] 0.0001 72.2 0.0011 72.1 0.0020 65.0 0.0023 60.60.0033 44.0 0.0038 26.8 0.0050 15.8 0.0100 15.7 0.10 15.4 1.00 15.4

TABLE 15 Bubble life [ms] γ[mN/m] 31 71.7 40 71.4 51 71.4 64 70.9 8470.9 111 70.9 144 70.4 186 70.4 244 70.1 322 69.8 398 69.7 525 69.6 71569.5 934 68.7 1221 67.7 1597 67.2 2099 66 2501 65.3 3243 64.3 4142 62.35208 61 7135 58.1 8938 55.7 11481 53.5 15165 50.3 19619 48.2 24941 46.133879 44 41071 41.8 54632 40.7

1. Compounds of the formula (I)

where the groups Z_(i) (Z₁, Z₂ and Z₃) are, independently of oneanother, branched or unbranched alkyl groups or groups of the structureR_(i)(A(CR¹R²)_(ci)—(CR³R⁴)_(c′i))_(di)—, where the respective indicesci and c′i are, independently of one another, 0-10 and di=0-5, whereR_(i) is a branched or unbranched, fluorine-containing alkyl radical, R¹to R⁴ are, independently of one another, hydrogen or a branched orunbranched alkyl group, ci and c′i are not simultaneously 0, and A=O, Sand/or N, Y₁ is an anionic polar group and Y₂ is a hydrogen atom, orvice versa, X is a cation, and at least one of the groups Z_(i) is agroup of the structure R_(i)(A(CR¹R²)_(ci)—(CR³R⁴)_(c′i))_(di)—. 2.Compounds according to claim 1, characterised in that the variables inthe formula (I) have the following meanings: the groups Z_(i) (Z₁, Z₂and Z₃) are, independently of one another, branched or unbranched alkylgroups or groups of the structure R_(i)(O(CH₂)_(ci))_(di), where therespective indices ci=2-10 and di=0-5, where R_(i) is a branched orunbranched, fluorine-containing alkyl radical, Y₁ is an anionic polargroup and Y₂ is a hydrogen atom, or vice versa, X is a cation, and atleast one of the groups Z_(i) is a group of the structureR_(i)(O(CH₂)_(ci))_(di).
 3. Compounds according to claim 1,characterised in that the unfluorinated, branched or unbranched alkylgroups contain 1 to 10, in particular 3 to 8, carbon atoms.
 4. Compoundsaccording to claim 1, characterised in that X is a monovalent cation, inparticular H⁺, or an alkali metal cation, in particular Na⁺, or NR₄ ⁺,where R=H⁺ or C1-C6-alkyl, in particular H⁺, and all R may be identicalor different.
 5. Compounds according to claim 1, characterised in thatthe compounds contain two or three, in particular three, fluorinatedgroups Z_(i).
 6. Compounds according to claim 1, characterised in thatZ₁, Z₂ and Z₃ are, independently of one another,F₃C(CF₂)_(ai)(CH₂)_(bi)(O(CH₂)_(ci))_(di)— groups, where ai=0-2, inparticular ai=1-2, bi=1-6, in particular bi=1-2, ci=2-10, in particularci=2, and di=0-5, in particular di=1, where, in particular, Z₁=Z₂=Z₃. 7.Compounds according to claim 1, characterised in that Y₁ or Y₂, inparticular Y₁, is a sulfonate group —SO₃ ⁻.
 8. Compounds according toclaim 1, characterised in thatZ₁=Z₂=Z₃=F₃C(CF₂)_(ai)(CH₂)_(bi)(O(CH₂)_(ci))_(di), where ai=1-2,bi=1-2, ci=2, and di=1, Y₁ is a sulfonate group —SO₃ ⁻, Y₂ is a hydrogenatom, and X=Na⁺.
 9. Compounds of the formula (Ia) or (Ib):

where Z₁=Z₂=Z₃ and all Z_(i) are selected from R_(i)(O(CH₂)_(ci))_(di),where ci=2, di=1-3, and R_(i)=CF₃CF₂CH₂— or CF₃CF₂CF₂CH₂—.
 10. Use ofcompounds according to Claim 1 as surface-active agents, in particularas additives in paint and coating preparations, printing inks and waxes,as well as polishes.
 11. Compositions, in particular paint and coatingpreparations, comprising at least one compound of the formula (I) and avehicle which is suitable for the particular application, and optionallyfurther specific active substances.
 12. Process for the preparation ofcompounds according claim 1, comprising a) the esterification ofaconitic acid or citric acid or the anhydride or acid chloride thereofusing one or more alcohols of the formula Z_(i)OH (II), preferably inthe presence of a catalyst, and b) the addition reaction, preferably ofsodium hydrogensulfite, onto the olefinic double bond or derivatisationof the OH group, where the alcohols contain groups Z_(i) according toclaim
 1. 13. Compounds of the formula (III)

where the groups Z_(i) (Z₁, Z₂ and Z₃) are, independently of oneanother, branched or unbranched alkyl groups or groups of the structureR_(i)(A(CR¹R²)_(ci)(CR³R⁴)_(c′i))_(di)—, where the respective indices ciand c′i are, independently of one another, 0-10 and di=0-5, where R_(i)is a branched or unbranched, fluorine-containing alkyl radical, R¹ to R⁴are, independently of one another, hydrogen or a branched or unbranchedalkyl group, and A=O, S and/or N, and at least one of the groups Z_(i)is a group of the structure R_(i)(A(CR¹R²)_(ci)(CR³R⁴)_(c′i))_(di)—, andci and c′i are not simultaneously
 0. 14. Compounds according to claim13, characterised in that Z₁, Z₂ and Z₃ are, independently of oneanother, F₃C(CF₂)_(ai)(CH₂)_(bi)(O(CH₂)_(ci))_(di)— groups, whereai=0-6, in particular ai=1-2, bi=1-6, in particular bi=1-2, ci=2-10, inparticular ci=2, and di=0-5, in particular di=1-3, where, in particular,Z₁=Z₂=Z₃.
 15. Use of compounds of the formula (III) as monomers orcomonomers in the synthesis of fluorinated polymers.